TiO_2纳米管的力学和电子学性质  

Mechanical and electronic properties of TiO_2 nanotubes

作　　者：林峰[1] 李缵轶[1] 王山鹰[1] 

机构地区：[1]清华大学物理系,北京100084

出　　处：《物理学报》2009年第12期8544-8548,共5页Acta Physica Sinica

摘　　要：基于密度泛函理论研究了纤铁矿和锐钛矿型TiO2纳米管的原子结构、稳定性、Young模量以及电子能带结构.计算结果显示:在纳米管直径较小时,锐钛矿型TiO2纳米管的稳定性要好于纤铁矿型纳米管,随着管径的增大,纤铁矿型纳米管变得比锐钛矿型纳米管要更稳定.纤铁矿型TiO2纳米管具有比锐钛矿型纳米管更大的Young模量,力学性能比较优异.另外,通过对电子能带结构的研究发现,手性对TiO2纳米管的电子结构影响较大,纤铁矿(0,n)型和锐钛矿(n,0)型纳米管为间接带隙半导体,而纤铁矿(n,0)型和锐钛矿(0,n)型纳米管却具有直接带隙.The structure,stability,Young＇s modulus and electronic band structures of lepidocrocite-type and anatase-type TiO2 nanotubes were investigated using density functional theory calculation. It was found that the anatase-type nanotubes were energetically more favorable than lepidocrocite-type nanotubes when the diameter of nanotube is small,whereas the lepidocrocite-type nanotubes were energetically more favorable when the diameter of nanotube was large. Young＇s modulus of TiO2 nanotubes is calculated. The results obtained show that all TiO2 nanotubes have relatively good mechanical properties,and lepidocrocite nanotubes are stronger than anatase nanotubes. Interestingly,it was found that the electronic band structures of TiO2 nanotubes are influenced by the tubular chirality. Lepidocrocite（0,n） and anatase（n,0） nanotubes are of indirect band gap type,whereas lepidocroctie（n,0） and anatase（0,n） nanotubes have direct band gaps.

关 键 词：TIO2纳米管 Young模量 间接带隙 直接带隙 

分 类 号：TB383.1[一般工业技术—材料科学与工程]